常压干燥法制备铁掺杂二氧化钛气凝胶

以钛酸四丁酯(TRIP)为原料、硝酸铁为掺杂剂、冰醋酸为催化剂、甲酰胺为干燥控制化学添加剂,采用溶胶-凝胶法制备Fe3+掺杂TiO2醇凝胶,并结合常压干燥工艺,实现了Fe3+掺杂TiO2气凝胶的常压干燥法制备.采用XRD、BET、SEM、IR等对样品进行检测.结果表明:制备态Fe3+掺杂TiO2气凝胶密度为0.24 g/cm3,比表面积为529.17 m2/g,平均孔径约为20.10 nm,晶型为无定形；经850℃空气气氛下煅烧2h后,样品转变为锐钛矿型结构,平均孔径增大到22.32 nm,比表面积为136.22 m2/g.通过甲基橙溶液光催化降解实验,相比未掺杂二氧化钛气凝胶,掺入nFe∶nTi=0.05时,样品具有更高的光催化性能.

Preparation of Fe Doped TiO2 Areogel by Ambient Pressure Drying

Monolithic TiO2 aerogels doped with iron was prepared by sol-gel method and subsequent process with ambient pressure drying using titanate tetrabutoxide,acetic acid and formamide as raw material.The structures of samples were characterized by means of XRD,BET,SEM and FT-IR et al.The results indicate that as-prepared iron-TiO2 aerogel is in amorphous state with bulk densities of 0.24 g/cm3,the specific surface area of 529.17 m2/g and average pore size of 20.10 nm.After calcined at 850 ℃ in air anatase is the main crystalling phase and the surface area is 136.22 m2/g.A test of photo-catalytic degradation in methyl orange solution finds that TiO2 aerogel doped with 0.05mol%of Fe3+ possesses a better catalytic efficiency compared with pure TiO2 aerogel.